1. Field of the Invention
The present invention is concerned with tubular bag-type packings and, in particular, it relates to so-called stickpacs formed from a sealable foil consisting of at least one layer.
2. Description of the Prior Art
Stickpacs of the afore-mentioned type are molded to form a tube provided with a longitudinal sealing joint extending between the side edges of the packing, with the tube being sealed by an upper and a lower transverse sealing joint. Packings of the afore-described type which are of a more or less slim tubular shape for which reason they are called stickpacs, have been disclosed, for example, by German Utility No. 93 12 664. A suitable plastic foil (which, depending of the contents, can also be multi-layered) is employed as the foil material for packings of this type in view of the sealability both of the longitudinal and of the transverse sealing joint. There are several options to design the longitudinal sealing joint, namely in the form of an overlapping seam, a folding seam or a butted seam. In packings wherein the longitudinal sealing joint is formed of abutting foil web edges, the latter are lined and sealed by a so-called inner sealing tape. The said tape, during molding on a shaping tube, automatically enters the tube.
Apart from the fact that stickpacs of the afore-described type can, of course, be transversely cut open by way of scissors, which, however, would not be desirable in sense of an easy handling also in respect of opening such packs, easy and simple ripping of such packs is intended. However, it has proved that this is rendered difficult by the double-layered longitudinal sealing joints because, as a rule, these cannot be readily torn. It should be noted that such stickpacs, for evacuating the contents thereof, frequently are taken directly into the user""s mouth; in such cases, the torn-off upper part with the longitudinal sealing joint still attached to the pack substantially affects a proper evacuation.
The provision of a tear groove on the lateral edge of the transverse sealing joints, namely on an expanded section of the transverse joint of the type provided in a bag-type pack according to German Utility Patent No. 43 22 572 is of no assistance to a satisfactory opening of such bag packs because the longitudinal sealing joint seam forms a tearing hindrance.
It is, therefore, a primary object of the present invention to provide a new and improved tubular bag-type packing in the form of a stickpac, wherein the longitudinal sealing joint no longer constitutes a tear hindrance.
A second object of the present invention is to provide a new and improved tubular bag-type packing in the form of a stickpac wherein the transverse sealing joint can be opened in whole while the sealed portion of the longitudinal joint is seized at the same time.
The foregoing and other objects are attained in accordance with one aspect of the invention through the provision of a tubular bag-type packing, wherein a tearing aid in the form of at least one groove is provided on the longitudinal joint in registry with an expanded section of the transverse sealing joint.
This configuration of the invention will remove the tear hindrance caused by the longitudinal sealing joint in that a tearing aid is now arranged pointedly and directly on the longitudinal sealing joint.
If the longitudinal joint is made of longitudinal edges of the foil that are sealed in overlapping relationship, the tearing aid is arranged on the inner foil edge and directed toward the transverse sealing joint.
If the longitudinal sealing joint is made of a so-called inner sealing tape and abutting foil edges, the tearing aid is provided on the inner sealing tape.
Feasibly, in both cases a tear groove may be provided, with advantage, on the longitudinal sealing joints within the expanded portion of the transverse joint, in registry with the tearing aids.
As to the second object mentioned hereinbefore, this object is attained in accordance with the present invention through the provision of a tubular bag-type packing, wherein, following at least one of the transverse welding seams, the tube is provided with an extension which, in turn, is furnished with a tearing aid on at least one of its longitudinal edges, and wherein the transverse joint provided with the extension is formed to extend at an inclination relative to the longitudinal axis or to the longitudinal joint of the tube.
The inclined transverse sealing joint can be in the form of an obtuse-angled seam the tip of which superposes the longitudinal sealing joint.
This will create above the transverse sealing joint two flaps easily seizable by thumb and forefinger of both hands so that when tearing apart these flaps the transverse sealing joint due to the inclined arrangement thereof, easily tears open. This is sort of a banana-type peeling of the pack no longer affected by the longitudinal welding seam.
As to the tearing aids provided on the extension, these can be formed by cut-open longitudinal edges or by perforated longitudinal edges or by laser scores provided on the longitudinal edges yet to be explained in closer detail hereinafter.